A number of systems have been developed for multiplexing optical fibercoupled transducers. Such systems include optical time division multiplexing, coherence multiplexing, and wavelength division multiplexing (WDM). Although all three systems have been demonstrated, WDM appears to offer the most promise for near term implementation in aircraft and other complex systems. In a WDM system, discrete spectral wavelength ranges or bands propagating along a fiber bus are modulated by one or,more of the sensors or transducers. A crucial component of a WDM system is a demultiplexer/detector, capable of receiving a broadband optical signal and of detecting the optical energy in different wavelength bands.